Research on Joint Clearing of Energy and Ancillary Service in Day-ahead Market Considering the Weights of Ancillary Services

Dong Mo ¹ Mingyuan Chen ¹ Qiuwen Li ¹ Youhui Yang ¹ Ziqiang Wang ² Xuefeng Zhu ^3*

• ¹ Guangxi Power Grid Corporation, Nanning, Guangxi Zhuang Region, China
• ² China Southern Power Grid (China), Guangzhou, Guangdong Province, China
• ³ Institute of New Energy, Wuhan, China, Wuhan, China

With the large-scale grid integration of new energy sources and the increasing number of new types of loads, the demand for ancillary services in the power system has been increasing. The coordinated operation mode of electric energy market and ancillary service market has become a key issue. A joint clearing method considering the weights of ancillary services is proposed, which combines the advantages of joint clearing and independent clearing. On the one hand, the method inherits the traditional advantages of joint clearing, which can minimize the overall cost and ensure the optimal allocation of resources; on the other hand, it also incorporates the beneficial characteristics of independent clearing, which means that in the event of a shortage of resources in the market, the normal clearing of electric energy and key ancillary services can be ensured, which makes the clearing result more targeted. On the other hand, it also incorporates the beneficial feature of independent clearing, i.e. in the event of a shortage of market resources, it can ensure the normal clearing of electric energy and key ancillary services, and make the clearing result more targeted. On this basis, a joint clearing day-ahead Security-Constrained Unit Commitment (SCUC) and Security-Constrained Economic Dispatch (SCED) model considering the weights of ancillary services are established. Finally, a case study of a power system containing traditional fossil energy and new energy is conducted to verify the correctness and effectiveness of the proposed new clearing model. 1total number of units